Clinicopathologic manifestations of early-onset endometrial cancer in Japanese women with a familial predisposition to cancer

Aim: The number of patients under 40 years of age with early-onset endometrial cancer is on the rise in Japan. Preservation of fertility in younger patients is a critical issue. In order to examine the clinical and pathological characteristics of these patients, cases of early-onset endometrial cancer at a single hospital were analyzed. Methods: Seventy-four patients were diagnosed with endometrial cancer before age 40 and included in this study after obtaining informed consent. Results: The clinical characteristics included a significantly higher prevalence of complications such as nulligravidity and nulliparity (P < 0.001). Pathologically, well-differentiated endometrial carcinoma was significantly more frequent (P = 0.011). The 5-year survival rate was high (98.7%). In regards to the relationship between clinicopathological features and grade of differentiation, the prevalence of G2 and G3 carcinoma was not significantly lower (P = 0.24) in patients with obesity. Although the frequency of G2 and G3 carcinoma was significantly higher in patients with a family history of cancer (P = 0.02), their 5-year survival rate was not significantly lower (100%). Conclusion: This study found that these two types of early-onset endometrial cancer are clinicopathologically different. In patients with a family history of cancer, their body mass index was lower, and the frequency of G2 and G3 carcinoma was significantly higher, but their 5-year disease-free survival rate was not significantly lower.